Textile finishing



Patented Dec. 23, 1941' PATENT TEXTILE FINISHING Onslow B. Hager, Glenside, Pa., assignor to Rohm & Haas Company, Philadelphia, Pa.

No Drawing. Application October 23, 1939, Serial No. 300,894

UNITED ST cries 4 Claims.

This invention represents an improvement in the finishing of fabrics with carbamide-aldehyde condensates. In particular it relates to preventing or correcting odor in fabric which has been treated with resin or resin-forming compositions of the urea-formaldehyde type.

Finishing fabrics with carbamide-aldehyde reaction products has recently become a relatively common practise, not only for producing anti-creasing effects or non-crushing effects, but for such diverse purposes as stabilizing cloth against shrinkage, preventing laddering and the pulling-out of seams, improving the handle and appearance, as shown by apparent bulk, smoothness, fullness, etc. When fabrics have been fully processed with proper care, no difiiculties have been encountered from the development of odors. From time to time, however, fabrics which have not been properly finished have been observed to possess or to develop odors. The faulty application of condensates of the urea-formaldehyde type may have been due Typical useful oxidizing agents which are suitable for this application include hydrogen peroxide, organic peroxides, the perborate salts, the percarbonate salts, the persulfates, etc. All such materials may be classified as peroxide-type i oxidizing agents. The perborates and the percarbonates, being salts of weak acids, give somewhat alkaline solutions by themselves. In case, however, that it is desired to render the solution definitely alkaline, particularly when hydrogen peroxide, an organic peroxide, or a persulfate is used, such mildly alkaline materials as sodium bicarbonate, soda ash, borax, or disodium phosphate, or mixtures of such materials, or mixtures of such materials with other alkaline reagents, such as metasilicate or trisodium phosphate, are preferred. In general any freely soluble, fixed, alkaline material may be used which will impart to the treating bath a pH between 7 and about 11. The treating bath may be used at any temperature from room temperature up to about 150 F.

to improper control of conditions, inadequate The proportions of oxidizing a n and alkaequipment or attempts t obtain economies by line reagent which are used are not critical but such means as insufiicient temperature or time should be adjusted in accord with the amount in curing or by omitting the tep of Washing of resin and catalyst used and with the rate at the treated fabric. It is frequently found im- Which the p e s s run. As more resin and practical to give the thorough wash whi h i catalyst are used, there is more material which necessary to ensure against odor when every must be acted upon With the d ng and alother condition has been correctly attained and kaline material. f the rate at which cloth is controlled. run through the solution is relatively low, the It is the main object of this invention to pro- Concentrations of r n s c n be lower than jde a, simple practical method for preventing when the rate of operation is faster. In genodor in fabrics processed with carbamide-aldeel'al, enough alkali should be used so that the hyde type condensates. It is also an object, to pH of cloth after treatment is on the alkaline overcome odor in fabric which has been treated Side, y about -5- In general the con- With urea-formaldehyde type reaction products. centratlons oxidizing a t and alkaline ma- It has been found that odor can be corrected term] each fall between and 2%, but lower or prevented by treating fabric containing resin and higher concentrations y a so be used. of the carbamide aldehyd type with a mild 4 For the finishing of fabrics there may be used oxidizing agent under alkaline conditions. In any of the Water-Soluble Organic solventthe most direct procedure the fabric which has soluble forms of urea-formaldehyde reaction been resimtreated, is passed or padded through products, such as methylol urea, dimethylol urea, a mildly alkaline, oxidizing solution and alcohol-urea-formaldehyde condensation prodmediately dried by any suitable means, such as or the urea-formaldehyde eaction loop drier, heated cans or enclosed tenter products modified with thiourea, dicyandiamide, frame. since t oxidizing solution may be melamine or its derivatives, etc. Such carbamplied at relatively high speeds, thi proce i ds-aldehyde reaction products may be applied more economical th th longer Washing with any of the usual catalysts such as acid salts, cedures which have heretofore been necessary. ammonium Salts, Organic acids, e e ay It is also more satisfactory because of dependalso be used Softening and modifying a nts. ability and uniformity of results. But, if des h as the qu t rna y a m nium compounds sired, the oxidizing step can be combined with with long chains, sulfonated oils or tallows, etc. v used in conjunction W the W hing pr The mechanism by which an alkaline oxidizleing solution overcomes odor may be postulated 2 in the following way, but the proposed explanation is not to be interpreted as limiting the invention. The type of odor which is due to loosely held formaldehyde is overcome by oxidation to formic acid which forms salts in the presence of alkaline agents. The types of odors, which are sometimes described as fish-like or mouse-like, and which apparently depend upon some obscure reaction of formaldehyde, ammonia, amines, or urea in the presence of an acid catalyst, are apparently prevented by oxidizing formaldehyde or similar sensitive compounds, removing ammonia and neutralizing the acidity.

A procedure by pared is shown in which odor-free fabric is prethe following examples:

Example 1 An 80 x 80, 4.00 yard, 36" bleached white cotton, woven fabric was impregnated with an aqueous solution containing 15% dimethylol urea and 0.3%- diammonium hydrogen phosphate. The impregnated fabric was squeezed between rolls so that it retained solution to the extent of 60% of its original dry weight, dried in a covered tenter at 300 F. for about one-half minute, batched, and cured in an oven at 320 F. for about one and one-half minutes. Due to this short period of cure, the fabric possessed a modified formaldehyde-like odor. through a solution at 120 F. containing one-half per cent. of 30% hydrogen peroxide and 0.3% of soda ash. The fabric was run at the rate of 80 yards per minute and squeezed so as to take up solution to the extent of about 60% of the weight of the fabric. It was then dried in a closed tenter at 300 F.

The processed fabric was free from any objectionable'odor. On storage there was no development of odor. Cloth, cured by the same general procedure but with omission of the treatment with a mild oxidizing agent in an alkaline bath, possessed an odor at the start and developed stronger and more objectionable odors on storage.

' Example 2 Rayon-pile, silk-backed, transparent velvet was impregnated on a quetch. with solution containing 25% of a water-soluble, urea-formaldehyde reaction product and 1% of diammonium phosphate ,as catalyst. The fabric was allowed to retaina weight of solution approximately equal to its dry weight. .The fabric was dried at a low temperature on a frame with brushing.

Curing was accomplished in a conveyor drier at about BOO-320 F. for four to eight minutes. The fabric was then washed on a rope washer for 15 minutes at 140 F. ina solution containing 1 lb. of octylphenoxyethoxyethoxyethyl sodium sulfonate, 6 oz. of trisodium phosphate, and 10 lbs. of 30% hydrogen peroxide in 500 gallons of water. The fabric was then opened up, passed over a vacuum bar extractor, passed. through a quetch supplying a solution containing 0.06% of cetyldimethylbenzyl ammonium chloride, over a vacuum bar extractor, and through a frame It was then run where the fabric was dried while being brushed. It was then given the usual finishing sheer. The resulting fabric was crush-resistant without pile embrittlement and had a smooth, silky hand, good bloom, excellent cover, no slippage, and uniform, full appearance without lay. There was no odor in the fabric immediately after processing nor after four months storage in a closed carton.

Example 3 A spun rayon suiting was treated by immersion in a solution containing 5% of methylol urea and 0.2% of diammonium phosphate and squeezed so as to obtain an pick-up of solution in the cloth. The cloth was dried on a set of steam-heated cans and the resin cured during passage through a closed tenter heated at 300-340 F., running at 60 yards per minute. The dried cloth was then padded at 120 yards per minute through a solution containing 4 lbs. of sodium perborate and 1 lb. of sulfonated teaseed oil in gallons of water and dried on a bank of cans. The cloth was finally passed through a Sanforizing machine to reduce shrinkage to less than 1%. By virtue ofv the resin treatment the actual shrinkage left for removal by the Sanforizing machine was reduced from 7% to 3%.

The suiting possessed a resilient, wool-like hand. It was free from all objectionable odors.

The process herein described may obviously be applied not only to fabrics which are being freshly processed but also to fabrics which have previously been finished and which have developed odor during storage.

I claim: a

l. The process of overcoming or preventing development of odor in textile fabrics carrying a finished resin of the urea-formaldehyde type which comprises treating the resin-carrying fabric with an aqueous solution having a pH between '7 and about 11 and containing a. small amount of. a water-soluble peroxide-type oxidizing. agent.

2. The. process of overcoming or preventing development of. odor in textile fabrics carrying. a resin of the urea-formaldehyde type which comprises treating the finished resin-carrying fabric with an aqueous solution having a pI-Lbetween 7 and about 11 and. containing hydrogen peroxide and drying the fabric.

3. The process of overcoming or. preventing development of odor in textile fabrics carrying a finished resin of the urea-formaldehyde type which. comprises treating the resin-carrying fabric. with a. dilute aqueous solution of sodium perborate and drying the fabric.

a. In the process ofv producing permanent finishes of textile fabrics with urea-formaldehyde type reaction products the improvement which comprises treating. fabric carrying insoluble. urea-formaldehyde reaction products with a solution having apl-l between 7 and about 11 and containing a water-soluble, peroxide-type oxidizing agent thereby to overcome or prevent sub- ONSLOW B. HAGER. 

